The specific aims of the UTMB Claude Pepper Older Americans Independence Center (OAIC) are to: 1) provide core support to funded translational research by UTMB investigators on muscle function and functional recovery in older adults; 2) Stimulate the growth of additional interdisciplinary translational research projects to improve muscle function and functional recovery in older adults by: a) funding pilot project research to generate preliminary data in promising new areas of investigation and b) funding developmental projects to develop innovative technologies; 3) Train future leaders in research in the mechanisms, prevention and treatment of muscle dysfunction and disability in older adults; 4) Recruit established investigators with expertise relevant to muscle function and functional recovery in older adults into interdisciplinary translational research related to the OAIC focusi and 5) Foster collaborations between UTMB investigators and investigators at other OAIC and other institutions on studies of muscle function and functional recovery in older adults. The theme for the next cycle of our OAIC is: Translating Biological Mechanisms of Muscle Growth and Loss to Improve Function and Recovery in Older Adults. Our focus is on translating basic discoveries on the mechanisms of muscle loss and re-growth with aging to clinical practice to promote functional recovery and prevent disability in older adults. Observational sutidies will provide crucial information for selecting appropriate in-hospital, post-discharge, and long-term outcomes for inclusion in clinical trials of geriatric patient populations. Our general hypothesis is that aging induces mild but significant changes in muscle biology and function that progressively lead to muscle loss and predispose to potentially catastrophic declines in muscle mass and function during bouts of acute illness. We also hypothesize that anabolic interventions involving exercise/rehabilitation, amino acid/protein supplementation and hormonal or other pharmacological treatment can prevent the age- and disease-induced muscle loss and reduce the risk of